Video conferencing via networks such as the Internet is becoming increasingly popular. Video conferences on the Internet are typically supported by a video conferencing server such as the Multipoint Conference Unit (MCU), manufactured, sold and licensed by First Virtual Communications, Inc. of Nashua, N.H. and Santa Clara, Calif. Participants in a video conference supported by such servers communicate via their local video conferencing client software over the Internet with the MCU, which provides the audio and/or video conferencing data to some or all of the participants. Typically, video conferences are initiated by one or more prospective participants communicating with the MCU, such as by visiting a dedicated website, to identify invitees to the conference. The MCU then initiates and supports the video conference by providing the appropriate conference data to the client associated with each of the identified participants through network links with each of the clients.
Instant messaging (IM) is becoming an increasingly popular utility on networks such as the Internet. Under instant messaging, IM clients on a network can communicate with each other via an IM server or messenger service of the network. The messenger service also typically provides a “presence” feature which permits IM clients to know the status of other clients on the network serviced by the messenger service. The status information for a client includes whether the client is online and available to receive instant messages from other clients and whether the client presently at his workstation, which can be determined by the level of activity at the client's workstation. The presence feature also allows clients to declare themselves unavailable to receive instant messages so that incoming messages can be blocked.
Because of the wide range of capabilities and the convenience of instant messaging, it is becoming a popular means of communication among clients on networks. For example, individual companies are using instant messaging utilities as their preferred means of communication among employees.